In vitro and in vivo properties of PLGA scaffolds incorporated with Copaiba oil-resin prepared by electrospinning

Author(s)

Ana Luiza Garcia Millás

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Química
• Defense date: 2016-09-23

Examining board members

Edison Bittencourt; Ivan Hong Jun Koh; Ana Maria Alvim Liberatore; Maria Jose Vieira Fonseca; Angela Maria Moraes

• Advisor: Edison Bittencourt

Abstract

The development of tissue substitutes for the treatment of injuries is a challenge in regenerative medicine and tissue engineering fields. There has been a growing demand for therapeutic alternatives, as well as the analysis of efficacy and stimulating healing process. Using the electrospinning technique, this thesis focuses on the development of a fibrous matrices, with uniform diameters and porosity adequate for three-dimensional cell growth, aiming to be applied as a dermal cells support, replacing or regenerating damaged or lost tissues. The scaffolds were produced using solutions of poly (lactic-co-glycolic acid) PLGA 50:50 dissolved in 1,1,1,3,3,3-hexafluoro-2 propanol (HFIP), a bioresorbable polymer, approved by the FDA regulatory agency. The scaffolds were incorporated with copaíba oil-resin (Copaifera langsdorffii), a phytotherapy from Amazon with proven therapeutic properties, anti-inflammatory, analgesic and antimicrobial. A comparative analysis between the scaffolds with oil and without oil-resin was performed. The interfaces scaffoldsl/cells were studied in vitro, and material/tissues was investigated in vivo. The in vitro assays showed cytocompatibility of the scaffolds without oil and cytotoxicity of the scaffolds with copaíba oil-resin. In the scaffolds without oil was proven the presence of collagen type I and type III deposited by the fibroblasts. Histopathological analyzes of the in vivo tests indicated that the rat tissues reacted positively to both scaffolds, in addition to being biocompatible, the material biointegrated to the subcutaneous and intramuscular animal tissues, and a new tissue was formed inside the implants. In the scaffolds with copaiba oil-resin intense angiogenesis was observed. No chronic inflammatory responses, necrosis, calcification, tumorogenesis or any type of infection were observed. Therefore, we conclude that: 1) the in vitro assays alone was not efficient to investigate the copaiba oil-resin action; 2) the three-dimensional pore structure of the scaffolds was essential to their biocompatibility and biointegration; 3) copaiba oil-resin promotes angiogenesis; 4) the fibrous matrices developed have potential for future application as a tissue substitute (AU)

• FAPESP's process: 12/09110-0 - Electrospinning technology for the development of embedded scaffolds with natural oils for skin regeneration
• Grantee: Ana Luíza Garcia Millás Massaguer
• Support Opportunities: Scholarships in Brazil - Doctorate